1. Field of the Invention
This invention relates to novel demulsifier compositions and to methods of using such compositions to demulsify. More particularly, the invention relates to novel demulsifying agents for use in processes adapted for preventing, breaking or resolving emulsions of the water-in-oil type, particularly petroleum emulsions and emulsions of water obtained in crude oil production.
2. Prior Art
A wide variety of oxyalkylated compounds are known to be demulsifiers for the resolution of water-in-oil emulsions. For example, it is well-known that effective demulsifiers can be prepared by condensation of diglycidyl ethers with polyoxylated glycols. U.S. Pat. Nos. 2,792,352; 2,792,353; 2,792,354; 2,792,355; 2,792,356; and 2,792,357 disclose that such demulsifiers are useful to resolve crude oil emulsions.
In U.S. Pat. No. 3,511,882, blends of oxyalkylated compounds and oxyalkylated adducts of phenol-formaldehyde resins, polyalkylene polyamines and the like are disclosed as being effective demulsifiers.
In U.S. Pat. No. 4,626,379 there is disclosed a now commercial demulsifier which comprises the partially condensed reaction product of a blend of at least two oxyalkylated materials with a vinyl monomer. Such oxyalkylated materials are, for example, polyoxyalkylene glycols, oxyalkylated phenolic resins and oxyalkylated polyamines. The disclosed vinyl monomers include acrylic and methacrylic acids and their esters, such as vinyl formate, vinyl acetate, vinyl propionate and the like, acrylonitrile, styrene and other vinyl aromatics, such as vinyl pyridine, vinyl pyrollidone, acrylamide, maleic anhydride and their esters, half esters and the like.
In U.S. Pat. No. 4,877,842 is disclosed a demulsifying composition comprising the reaction product resulting from subjecting to grafting reaction conditions a mixture comprising a solvent, a polyoxyalkylene amine and a vinyl monomer to produce a grafted intermediate and subjecting said grafted intermediate to esterification is partially cross-linked.
Despite the fact that many demulsifiers have been disclosed for resolving water-in-oil emulsions, the oil processing and servicing industries are continually looking for more effective demulsifiers, ones that will demulsify a given emulsion at reduced dosages and/or ones that are more economical to produce and use.
An objective of the present invention is to provide novel, more cost effective demulsifiers.